Environmental Engineering Reference
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as well as Southeast Asia, but the process reached its greatest and most worrisome
extent in Amazonia, the world's most extensive tropical forest, shared by Brazil,
Venezuela, Colombia, Ecuador, Peru, and Bolivia, where large-scale conversions
were rare before 1970.
The i rst decade of accelerated Amazonian deforestation (enabled by new road
construction and encouraged by the government) was concentrated most heavily
in Rondônia, Mato Grosso, and Pará and coincided with the launching of the i rst
Earth-observation satellites: their imagery showed a herringbone pattern of defor-
estation progressively thickening along newly cut roads. Pre-deforestation Amazo-
nian forest covered about 4.1 Gha, and the additional nearly 850 Mha of cerrado
and 92 Mha of inland water surfaces made up roughly 5 Gha of what is considered
in Brazil the “legal Amazon.” The total deforestation before 1970 amounted to no
more than 35 Mha; in contrast, by 1978 nearly 80 Mha of forest were cleared and
an additional 130 Mha included trees isolated by progressing cutting and exposed
along its edges; a decade later these two totals rose, respectively, to 230 and nearly
360 Mha, their total prorated to an annual loss of 1.5 Mha (15,000 km 2 , an area
smaller than Kuwait) and the lost and disturbed area amounted to nearly 12% of
the legal Amazon (Skole and Tucker 1993).
Deforestation rates increased during the 1990s and they remained high during
the i rst i ve years after 2000: between 1996 and 2005 Amazonia lost 19.5 Mha,
with cuttings moving deeper into the heart of the region in the states of Acre and
Amazonas. That is why a changed attitude of the Brazilian government, rel ected
by recent statistics, is perhaps the most promising development in an overwhelm-
ingly depressing realm of tropical tree loss: in 2008 it announced its target to cut
deforestation rates to 20% of their 1996-2005 level, and between 2005 and 2009
they had already fallen by 36% (Nepstad et al. 2009). An important part of this
effort has been to put 51% of the remaining forest into various parks and reserves.
But nothing will come easily. In 2009 a group of Brazilian and U.S. researchers
thought that the end of deforestation in the Brazilian Amazon was a real possibility
within a decade (Nepstad et al. 2009). Just two years later satellite monitoring in
March and April 2011 recorded destruction of 593 km 2 , or a 473% increase in
cleared area compared to the same months of 2010 (INPE 2011). And in April 2012
the lower house of Brazil's National Congress passed a bill whose provision could
greatly reduce forest protection and reaccelerate deforestation (Tollefson 2012).
The last decade of the twentieth century and the i rst decade of the twenty-i rst
century have also seen very high deforestation rates in Southeast Asia (particularly
in Indonesia's Kalimantan and Sumatra, in Thailand, and in Myanmar) and in parts
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